Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Dicyandiamide curing agent

Figure 2.8 Scanning electron micrograph of unidirectional glass epoxy laminate containing residual dicyandiamide curing agent. After prolonged exposure to hot water, cracks propagated from where the particles had been before they dissolved in the water... Figure 2.8 Scanning electron micrograph of unidirectional glass epoxy laminate containing residual dicyandiamide curing agent. After prolonged exposure to hot water, cracks propagated from where the particles had been before they dissolved in the water...
The consequence of soluble inclusions for moisture absorption is shown in Fig. 3.4, where the effect of residual dicyandiamide curing agent (DICY)... [Pg.83]

Cyanamide and its aromatic derivative, such as 4,4 -methylene bis(phenyl cyanamide), were reported to cure an epoxy resin at elevated temperatures.(4) It is also well known that the dimer of cyanamide (dicyandiamide) is the most important epoxy curing agent in one-package epoxy compounding.(5) Unfortunately, this dimer precipitates from the dispersion causing uneven mixing upon standing. [Pg.106]

Figure 2.13. Dependencies of the rate constant of a reaction K and the constant of self-acceleration co on the concentration of a curing agent (dicyandiamide). Figure 2.13. Dependencies of the rate constant of a reaction K and the constant of self-acceleration co on the concentration <t> of a curing agent (dicyandiamide).
The catalytic curing agents commonly used include tertiary amines, Lewis acids and bases, and dicyandiamide. Since their function is truly catalytic, the catalyst is added at relatively low concentrations (0 to 5% by weight) to the epoxy formulation. Homopolymerization generally requires both the presence of catalysts and elevated temperatures for the reaction to proceed. Like the polyaddition reaction, the homopolymerization reaction is accelerated by hydroxyl groups or tertiary amines. [Pg.38]

Benzyldimethylamine (BDMA) is another tertiary amine that can be used as either a sole catalyst or an accelerator with other curing agents. It is used with DGEBA epoxy resins at 6 to 10 pph. The pot life is generally 1 to 4 h, and the cure will be complete in about 6 days at room temperature. When used by itself, BDMA can provide epoxy adhesive formulations with high-temperature resistance (Chap. 15). However, BDMA is mostly used as an accelerator for anhydride and dicyandiamide cured epoxy resins. [Pg.104]

Table 12.9 shows a formulation for an accelerated general-purpose one-component, dicyandiamide cured epoxy adhesive compared to one with a modified aliphatic amine curing agent. Notice that the dicyandiamide cured system provides a higher glass transition tem-... [Pg.235]

The BF3-MEA complex offers a slightly faster rate of cure and a reduced shelf live in liquid epoxy systems when compared to unaccelerated dicyandiamide cured epoxy formulations. However, when used as a sole curing agent, BF3-MEA has not had the commercial success of dicyandiamide because of their lower bond strength and brittleness. The BF3-MEA complex compounds also hydrolyze in the presence of moisture, so that mixtures with epoxy resins must be stored in tightly closed containers to maintain shelf life. [Pg.236]

Latent curing agents such as dicyandiamide are dissolved into solvent solutions of solid epoxy resins. This is then followed by evaporation of the solvent. [Pg.243]

Similar information is presented in Table 14.5 for starting adhesive formulations made from an epoxy resin emulsion and dicyandiamide latent curing agent. This adhesive has exceptionally good water resistance when cured. The adhesive was applied to the indicated substrates in a manner similar to that described above, and it was cured for 3 min at 65°C followed by 10 min at 175°C. [Pg.267]

Overheating of the adhesive is always a critical concern with induction curing. This is especially true when the adhesive cures with a high exotherm, such as epoxy-dicyandiamide systems. Several proprietary epoxy curing agents have been developed that provide lower exotherm yet faster cure rate than typical dicyandiamide reactions.27,28 Tertiary amines and modified polyamines29 are often used to accelerate the cure of dicyandiamide-epoxy... [Pg.275]

In addition to fingerprinting matrix systems, IR can also be used to quantitatively assess certain formulative components. Dicyandiamide and DDS, two important curing agents in today s technology, can be measured quantitatively with this technique. [Pg.6]

Resin I contains roughly equal amounts of diglycidyl ether of bisphenol A (DGEBA) and an epoxy cresol novolac. Sufficient dicyandiamide (DICY) as a curing agent is present such that the amine/epoxy ratio is 0.85. Monuron is present as an accelerator. The supplier s recommend standard cure is two hours at 127°C. Previous work (1 ) has shown that this cycle produces a fully cured system, as indicated by the disappearance of the epoxide absorbance band in the infrared spectrum. [Pg.571]

Typically, a low molecular weight solid epoxy resin and latent curing agent, such as dicyandiamide dissolved in an appropriate solvent, are widely used in dry lay-up formulations for electrical laminates for computers, aerospace applications, and communications equipment. Wet lay-up systems are almost exclusively based on low-viscosity resins cured with aliphatic amines. These ambient cure resin systems are used primarily for manufacture of large chemical-resistant tanks, ducting, and scrubbers. Filament winding is used... [Pg.959]

Curezol . [Air Prods. Paciflc Anchor Anchor UK] Imidazoles epoxy curing agent for a esives, composites, filament winding, solder-resistant inks, potting compds., insulating powds., transfer molding powds. accelerator for dicyandiamide and anhydrides. [Pg.93]

AI3-50034 EINECS 211-581-7 Imidazole, 2-phenyl- IH-lmidazole, 2-phenyl- NSC 255226 Phenylimidazole 2-Phenylimidazole 2-Phenyl-IH-imidazole. Epoxy curing agent for printed circuit boards, molding compounds, potting accelerator for dicyandiamide and anhydrides. Leaflets mp = 1469.3° bp = 340° insoluble in H2O, very soluble in EtOH. BASF Cap. Janssen Chimica Lancaster Synthesis Co. [Pg.490]

Chem. Descrip. 2-Methyl imidazole CAS 693-98-1 EINECS/ELINCS 211-765-7 Uses Curing agent tor printed circuit board laminates, powd. coatings, adhesives, encapsulation accelerator for dicyandiamide and anhydrides Properties Pale yel. powd. m.w. 82 dens. 8.4 Ib/gal m.p. 137-145 C Imidazoline 18 DA [Lakeland Labs Ltd]... [Pg.433]

Uses Epoxy curing agent for printed circuit boards, molding compds., potting accelerator for dicyandiamide and anhydrides Manuf./Distrib. Aldrich http //www.sigma-aidrich.com, BASF http //www.basf.com, Schweizerhall http //www.susinc.com Trade Name Synonyms Curezol 2PZ t[Air Prods./Perf. Chems. http //WWW. airproducts. com] 2-Phenyl-2-imidazoline CAS 936-49-2... [Pg.3321]

See other pages where Dicyandiamide curing agent is mentioned: [Pg.41]    [Pg.132]    [Pg.100]    [Pg.1488]    [Pg.5048]    [Pg.363]    [Pg.41]    [Pg.132]    [Pg.100]    [Pg.1488]    [Pg.5048]    [Pg.363]    [Pg.514]    [Pg.321]    [Pg.372]    [Pg.443]    [Pg.422]    [Pg.52]    [Pg.233]    [Pg.233]    [Pg.233]    [Pg.236]    [Pg.236]    [Pg.246]    [Pg.266]    [Pg.43]    [Pg.563]    [Pg.949]    [Pg.481]    [Pg.91]    [Pg.94]    [Pg.94]    [Pg.229]    [Pg.229]    [Pg.3]    [Pg.821]    [Pg.349]   
See also in sourсe #XX -- [ Pg.157 , Pg.159 , Pg.161 ]



SEARCH



Curing agent

Dicyandiamid

Dicyandiamide

Epoxy resin curing agents Dicyandiamide

© 2024 chempedia.info